Experiment with adjusting heights, widths, and borders to customize the dimensions as desired.
body {
padding: 150px 150px;
}
/* Customize the horizontal part of the ribbon */
.fribbon {
padding: 0 25px;
height: 60px;
background: #e7e7e7;
position: relative;
float: left;
clear: left;
}
/* Personalize the vertical part of the ribbon */
.fribbon:after {
content: "";
display: block;
width: 40px;
height: 0px;
position: absolute;
right: 0;
bottom: 0px;
z-index: 20;
border-bottom: 60px solid #e7e7e7;
border-right: 60px solid transparent;
/* Browser-specific styling */
-webkit-transform: rotate(90deg);
-webkit-transform-origin: right bottom;
-moz-transform: rotate(90deg);
-moz-transform-origin: right bottom;
-o-transform: rotate(90deg);
-o-transform-origin: right bottom;
-ms-transform: rotate(90deg);
-ms-transform-origin: right bottom;
transform: rotate(90deg);
transform-origin: right bottom;
}
/* Add a shadow effect to the ribbon */
.fribbon:before {
content: "";
display: block;
width: 20px;
height: 0px;
position: absolute;
right: 0;
bottom: 0px;
z-index: 10;
border-bottom: 60px solid rgba(0, 0, 0, 0.3);
border-right: 60px solid transparent;
/* Browser-specific styling */
-webkit-transform: rotate(80deg);
-webkit-transform-origin: right bottom;
-moz-transform: rotate(80deg);
-moz-transform-origin: right bottom;
-o-transform: rotate(80deg);
-o-transform-origin: right bottom;
-ms-transform: rotate(80deg);
-ms-transform-origin: right bottom;
transform: rotate(80deg);
transform-origin: right bottom;
}
<div class="fribbon"></div>